Re: [PATCH net-next] net: phy: at803x: remove at803x_aneg_done()

From: Vladimir Oltean <olteanv@gmail.com>
To: Michael Walle <michael@walle.cc>
Cc: Heiner Kallweit <hkallweit1@gmail.com>,
	netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
	Andrew Lunn <andrew@lunn.ch>,
	Russell King <linux@armlinux.org.uk>,
	"David S . Miller" <davem@davemloft.net>,
	Jakub Kicinski <kuba@kernel.org>
Subject: Re: [PATCH net-next] net: phy: at803x: remove at803x_aneg_done()
Date: Thu, 18 Mar 2021 19:04:01 +0200	[thread overview]
Message-ID: <20210318170401.mvvwryi7exouyrzy@skbuf> (raw)
In-Reply-To: <ae201dadd6842f533aaa2e1440209784@walle.cc>

On Thu, Mar 18, 2021 at 05:38:13PM +0100, Michael Walle wrote:
> Am 2021-03-18 17:21, schrieb Heiner Kallweit:
> > On 18.03.2021 16:17, Vladimir Oltean wrote:
> > > On Thu, Mar 18, 2021 at 03:54:00PM +0100, Heiner Kallweit wrote:
> > > > On 18.03.2021 15:23, Michael Walle wrote:
> > > > > at803x_aneg_done() is pretty much dead code since the patch series
> > > > > "net: phy: improve and simplify phylib state machine" [1].
> > > > > Remove it.
> > > > >
> > > >
> > > > Well, it's not dead, it's resting .. There are few places where
> > > > phy_aneg_done() is used. So you would need to explain:
> > > > - why these users can't be used with this PHY driver
> > > > - or why the aneg_done callback isn't needed here and the
> > > >   genphy_aneg_done() fallback is sufficient
> > >
> > > The piece of code that Michael is removing keeps the aneg reporting as
> > > "not done" even when the copper-side link was reported as up, but the
> > > in-band autoneg has not finished.
> > >
> > > That was the _intended_ behavior when that code was introduced, and
> > > you
> > > have said about it:
> > > https://www.spinics.net/lists/stable/msg389193.html
> > >
> > > | That's not nice from the PHY:
> > > | It signals "link up", and if the system asks the PHY for link details,
> > > | then it sheepishly says "well, link is *almost* up".
> > >
> > > If the specification of phy_aneg_done behavior does not include
> > > in-band
> > > autoneg (and it doesn't), then this piece of code does not belong
> > > here.
> > >
> > > The fact that we can no longer trigger this code from phylib is yet
> > > another reason why it fails at its intended (and wrong) purpose and
> > > should be removed.
> > >
> > I don't argue against the change, I just think that the current commit
> > description isn't sufficient. What you just said I would have expected
> > in the commit description.
>
> I'll come up with a better one, Vladimir, may I use parts of the text
> above?

My words aren't copyrighted, so feel free, however you might want to
check with Heiner too for his part, you never know.